package org.aisen.android.support.textspan;

import android.os.Handler;
import android.text.Layout;
import android.text.NoCopySpan;
import android.text.Selection;
import android.text.Spannable;
import android.text.method.MovementMethod;
import android.text.method.ScrollingMovementMethod;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewConfiguration;
import android.widget.TextView;

import org.aisen.android.common.utils.Logger;

/**
 * support long click
 * <p/>
 * A movement method that traverses links in the text buffer and scrolls if
 * necessary. Supports clicking on links with DPad Center or Enter.
 */
public class MyLinkMovementMethod extends ScrollingMovementMethod {

	private static final int CLICK = 1;
	private static final int UP = 2;
	private static final int DOWN = 3;

	private boolean mHasPerformedLongPress;
	private CheckForLongPress mPendingCheckForLongPress;

	private boolean pressed;

	@Override
	protected boolean handleMovementKey(TextView widget, Spannable buffer, int keyCode, int movementMetaState, KeyEvent event) {
		switch (keyCode) {
		case KeyEvent.KEYCODE_DPAD_CENTER:
		case KeyEvent.KEYCODE_ENTER:
			if (KeyEvent.metaStateHasNoModifiers(movementMetaState)) {
				if (event.getAction() == KeyEvent.ACTION_DOWN && event.getRepeatCount() == 0 && action(CLICK, widget, buffer)) {
					return true;
				}
			}
			break;
		}
		return super.handleMovementKey(widget, buffer, keyCode, movementMetaState, event);
	}

	@Override
	protected boolean up(TextView widget, Spannable buffer) {
		if (action(UP, widget, buffer)) {
			return true;
		}

		return super.up(widget, buffer);
	}

	@Override
	protected boolean down(TextView widget, Spannable buffer) {
		if (action(DOWN, widget, buffer)) {
			return true;
		}

		return super.down(widget, buffer);
	}

	@Override
	protected boolean left(TextView widget, Spannable buffer) {
		if (action(UP, widget, buffer)) {
			return true;
		}

		return super.left(widget, buffer);
	}

	@Override
	protected boolean right(TextView widget, Spannable buffer) {
		if (action(DOWN, widget, buffer)) {
			return true;
		}

		return super.right(widget, buffer);
	}

	private boolean action(int what, TextView widget, Spannable buffer) {
		Layout layout = widget.getLayout();

		int padding = widget.getTotalPaddingTop() + widget.getTotalPaddingBottom();
		int areatop = widget.getScrollY();
		int areabot = areatop + widget.getHeight() - padding;

		int linetop = layout.getLineForVertical(areatop);
		int linebot = layout.getLineForVertical(areabot);

		int first = layout.getLineStart(linetop);
		int last = layout.getLineEnd(linebot);

		MyURLSpan[] candidates = buffer.getSpans(first, last, MyURLSpan.class);

		int a = Selection.getSelectionStart(buffer);
		int b = Selection.getSelectionEnd(buffer);

		int selStart = Math.min(a, b);
		int selEnd = Math.max(a, b);

		if (selStart < 0) {
			if (buffer.getSpanStart(FROM_BELOW) >= 0) {
				selStart = selEnd = buffer.length();
			}
		}

		if (selStart > last)
			selStart = selEnd = Integer.MAX_VALUE;
		if (selEnd < first)
			selStart = selEnd = -1;

		switch (what) {
		case CLICK:
			if (selStart == selEnd) {
				return false;
			}

			MyURLSpan[] link = buffer.getSpans(selStart, selEnd, MyURLSpan.class);

			if (link.length != 1)
				return false;

			link[0].onClick(widget);
			break;

		case UP:
			int beststart,
			bestend;

			beststart = -1;
			bestend = -1;

			for (int i = 0; i < candidates.length; i++) {
				int end = buffer.getSpanEnd(candidates[i]);

				if (end < selEnd || selStart == selEnd) {
					if (end > bestend) {
						beststart = buffer.getSpanStart(candidates[i]);
						bestend = end;
					}
				}
			}

			if (beststart >= 0) {
				Selection.setSelection(buffer, bestend, beststart);
				return true;
			}

			break;

		case DOWN:
			beststart = Integer.MAX_VALUE;
			bestend = Integer.MAX_VALUE;

			for (int i = 0; i < candidates.length; i++) {
				int start = buffer.getSpanStart(candidates[i]);

				if (start > selStart || selStart == selEnd) {
					if (start < beststart) {
						beststart = start;
						bestend = buffer.getSpanEnd(candidates[i]);
					}
				}
			}

			if (bestend < Integer.MAX_VALUE) {
				Selection.setSelection(buffer, beststart, bestend);
				return true;
			}

			break;
		}

		return false;
	}

	@Override
	public boolean onTouchEvent(TextView widget, Spannable buffer, MotionEvent event) {

		int action = event.getAction();

		if (action == MotionEvent.ACTION_UP || action == MotionEvent.ACTION_DOWN) {
			Logger.e("OnTouchListener--->" + "MyLinkMoveMentMethod");
			
			int x = (int) event.getX();
			int y = (int) event.getY();

			x -= widget.getTotalPaddingLeft();
			y -= widget.getTotalPaddingTop();

			x += widget.getScrollX();
			y += widget.getScrollY();

			Layout layout = widget.getLayout();
			int line = layout.getLineForVertical(y);
			int off = layout.getOffsetForHorizontal(line, x);

			MyURLSpan[] link = buffer.getSpans(off, off, MyURLSpan.class);

			if (link.length != 0) {
				if (action == MotionEvent.ACTION_UP) {
					if (!mHasPerformedLongPress) {
						link[0].onClick(widget);
					}
					pressed = false;
				} else if (action == MotionEvent.ACTION_DOWN) {
					pressed = true;
					checkForLongClick(link, widget);
					Selection.setSelection(buffer, buffer.getSpanStart(link[0]), buffer.getSpanEnd(link[0]));
				}
				
				return true;
			} else {
				Selection.removeSelection(buffer);
			}
		}

		if (action == MotionEvent.ACTION_MOVE) {
			pressed = false;
		}

		return super.onTouchEvent(widget, buffer, event);
	}

	private void checkForLongClick(MyURLSpan[] spans, View widget) {
		mHasPerformedLongPress = false;
		mPendingCheckForLongPress = new CheckForLongPress(spans, widget);
		new Handler().postDelayed(mPendingCheckForLongPress, ViewConfiguration.getLongPressTimeout());
	}

	class CheckForLongPress implements Runnable {
		MyURLSpan[] spans;
		View widget;

		public CheckForLongPress(MyURLSpan[] spans, View widget) {
			this.spans = spans;
			this.widget = widget;
		}

		public void run() {
			if (isPressed()) {
				spans[0].onLongClick(widget);
				mHasPerformedLongPress = true;

			}
		}

	}

	private void performLongClick() {

	}

	public boolean isPressed() {
		return pressed;
	}

	@Override
	public void initialize(TextView widget, Spannable text) {
		Selection.removeSelection(text);
		text.removeSpan(FROM_BELOW);
	}

	@Override
	public void onTakeFocus(TextView view, Spannable text, int dir) {
		Selection.removeSelection(text);

		if ((dir & View.FOCUS_BACKWARD) != 0) {
			text.setSpan(FROM_BELOW, 0, 0, Spannable.SPAN_POINT_POINT);
		} else {
			text.removeSpan(FROM_BELOW);
		}
	}

	public static MovementMethod getInstance() {
		if (sInstance == null)
			sInstance = new MyLinkMovementMethod();

		return sInstance;
	}

	private static MyLinkMovementMethod sInstance;
	private static Object FROM_BELOW = new NoCopySpan.Concrete();
}
